M9

The M9 is the designation assigned by the United States military to the Beretta 92FS semi-automatic pistol following its adoption as the standard American service sidearm in 1985, replacing the Colt M1911A1 after 74 years of continuous service. The M9’s selection followed a competitive military trial—Joint Service Small Arms Program—in which the Beretta design was evaluated against several other candidates for the criteria of reliability, accuracy, safety, and durability that the military specified. The 9mm chambering that came with the Beretta adoption also marked a transition from the traditional .45 ACP to NATO-standard 9mm Parabellum, aligning American military sidearm ammunition with that of allied forces.

The M9 was initially issued to the U.S. Army, Air Force, Navy, and Marine Corps, though the adoption met significant resistance from within the military establishment and from firearms commentators who objected to replacing the proven .45 ACP 1911 with a 9mm pistol from a foreign manufacturer. These objections were partly addressed by the establishment of Beretta USA’s manufacturing facility in Accokeek, Maryland, which produces M9 pistols under American labor and management, and by subsequent ballistic testing that supported the adequacy of modern 9mm ammunition for military purposes.

The M9 served in the Gulf War, operations in Somalia, the conflicts in Iraq and Afghanistan, and numerous other operations over its three decades as the primary American military sidearm, accumulating an extensive and largely positive service record despite periodic criticism of its ergonomics and the challenges some users experienced with its double-action first shot trigger.

The M9 was officially replaced in U.S. military service by the SIG Sauer M17/M18 (P320) following a competitive trial concluded in 2017, ending a 32-year service history. Military-marked M9 pistols are collected as historically significant pieces of late 20th and early 21st-century American military history.